Crx will not try to reconnect to the database if the connection is lost. In your CRX error.log you have am entry such as:
01.12.2007 22:05:04 *ERROR* BundleDbPersistenceManager: failed to read bundle: c1220c96-71a4-4dc7-9183-b11e882ec0a4: java.sql.SQLException: Io exception: Connection reset (BundleDbPersistenceManager.java, line 1033)
CRX does not try to establish the connection to the db when the connection is lost.
Install CRX hotfix # 15973
Crx 1.3.1 and earlier versions of CRX